<template>
    <div>
        <p>Message的值是: {{ message }}</p>
        <p>obj.message的值是: {{ obj.message }}</p>
    </div>
</template>

<script setup>
import {reactive, toRef} from 'vue'
const obj = reactive({message: '会当凌绝顶'})
const message = toRef(obj,'message')

setTimeout(() => {message.value = '一览众山小'}, 2000)
</script>